Improvement in saws



` l My invention relatesto improvements in saw-teethy having eurvedbases, of such a iorm that the teeth v will jam themselves fast in the blade on pressure b`eing applied'to the points; and

` tooth as it appears when being introduccdto its place the patent granted to James W. Strange, August 13,

JOHN SMITH, 0F PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HENRY lDUISST'ON AND HAMILTON DISSTON, OF SAME PLAGE.`

Letters Patent No. 108,059, dated (ictober 4, 1870'.

-i-MPRovEMeNT In saws.

The Schedule referred to in these Letters Patent and part'of the same.

I, J OHN SMITH, of Philadelphia, county of Philadelphia, State of Pennsylvania, have invented an Improvementin Saws and inDetaehable Teeth for the same. of which the following is a specification.

Nata-rc cmd Object `of the Invention.

`My invention consists of a projection on the blade so arranged as to be struck by a projecting part of the tooth, thereby limiting the movement of the latter, and'preventing the expansion of the blade.

Description of the Accompanying Draw'np. Figure l is a sideview of myimproved detachable in the blade'.

Figure 2, the saine, showing the tooth fitted to its place.

General Desciption.4

1in-figs. 1 and 2, A represents part of the blade, and B, a detachable tooth, the base of the latter, as well as the recess ofthe bladein which the base iits, heilig formed on such a .curved lin'e that the tooth will jam itself fast in the blade on pressure being applied to the point a of the tooth.I

This arrangement of' self-binding tootn 1s shown in 1867, reissued to Henry Disston, September 28,1869.

The defeet'of this tooth is, that when the saw is in use, constant pressure must,4 necessarily be applied to the point, and the base becomes jammed solftight as to affect, by a wedge-likeaction, the integrity of the blade, which eventually becomes so much warped that the saw is rendered useless. I

In order to prevent this, rivets have been used, but these are also apt to distort the blade. I have found that the most effective remedy for these defects is theformation of a hooked-like projection or stop, b, on the blade in front of the tooth, the

front rounded endclof the toothbasefitting fnngly -into the'concavity ci' this projection, as shown in fig. 2.

The tooth and its recess are so arranged that when the further backward movement of' the tooth isar rested by the projection the hase'is suiieiently'tight in its recess, but Ano pressure applied to the point of the toothean canse the base to move further, or, by a wedge-like action, warp the blade.

Whatever yielding or springing of the tooth there may be, and there is always more or less of' this, it only tends to tighten the base in its recess without distorting the blade. i

It should be understood that the base of the tooth has a Vshaped groove, adapted to a similarlyshaped rib on the edge of the recess of the blade.

The projection b on the blade A, and the projec- Ation d on the tooth B, abutting therewith, as described. Intestimony whereof, I have signed my name to this specication in the presence of two snhsc ibing witnesses.

JOHN SMI IF. Witnesses: l l

A. H. SHQEMAKER, W. J. R. Denain.A 

